LTC1981/LTC1982

1

APPLICATIO S

DESCRIPTIO

FEATURES

The LTC

N-channel MOSFET drivers. An internal voltage tripler

allows gates to be driven without the use of any external

components. Internal regulation circuitry allows quies-

cent current to drop to 10

µAperdriver(20µAforLTC1981)

once the gates are charged.

Low quiescent current and low shutdown current (under

1

µA) make these parts ideal for battery and other power

constrained systems. The wide input voltage range ac-

commodates a variety of battery/input configurations.

Gate drive is internally clamped to 7.5V providing protec-

tion to the external MOSFET gate. The MOSFETs can be

driven in either high side or low side mode.

The LTC1981 single driver version also includes a gate

drive ready pin and twice the drive current capacity of the

dual driver LTC1982.

The LTC1981 is available in a 5-pin SOT-23. The LTC1982

is available in a 6-pin SOT-23.

s

Cellular Telephones

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Portable POS Terminal

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Handheld Battery Powered Equipment

, LTC and LT are registered trademarks of Linear Technology Corporation.

s

No External Components Required

s

Internal Voltage Triplers Produce High Side

Gate Drive for Logic Level FETs

s

Ultralow Power:

10

µA Per Driver ON Current (LTC1982)

20

µA ON Current (LTC1981)

<1

µA Shutdown Current

s

s

Gate Drive Outputs Driven to Ground During

Shutdown

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Gate Drive Outputs Internally Clamped to 7.5V Max

s

“Gate Drive Ready” Output (LTC1981)

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Ultrasmall Application Circuit

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5-Pin SOT-23 Package (LTC1981)

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6-Pin SOT-23 Package (LTC1982)

Single and Dual Micropower

High Side Switch Controllers

in SOT-23

GATE

SHDN

GND

GDR

LTC1981

LOAD

+

10

µF

GATE

DRIVE

READY

SHDN

1.8V TO 5.0V

54

123

1981/82 TA01

100k

Q1

Si3442DV

GATE 1 GATE 2

SHDN 1

SHDN 2

GND

LTC1982

LOAD 1

LOAD 2

+

10

µF

SHDN 1

SHDN 2

1.8V TO 5.0V

654

123

1981/82 TA02

Q1

1/2 Si6925DQ

Q2

1/2 Si6925DQ

Single High Side Switch Controller

Dual High Side Switch Controller